1. Field of the Invention
The present invention relates to a remote pointing apparatus, and more particularly, to a remote pointing apparatus including a remote controller, which generates an optical signal that is periodically expanded and/or reduced around the origin, and optical sensors that detect whether the optical signal is received.
2. Description of the Related Art
Remote pointing apparatuses are provided for digital televisions (DTVs) or web TVs so that searching program information, controlling a browser, or selecting a menu can be remotely performed using a remote controller. Conventional remote pointing apparatuses have a type of a touch pad or joystick. A touch pad type has a very low resolution and thus has difficulty with precision control. A joystick type is inconvenient for users because it is necessary to move a cursor to a point to be selected.
A mouse that is used for an existing computer can be used as a remote pointing apparatus. However, since a mouse requires a flat ground on which it rests and moves, even if the mouse operates in a wireless mode, it is inconvenient to freely use the mouse in a large room, e.g., a living room.
There has also been proposed a laser mode in which a user can intuitively point at a desired position using a laser beam. However, a light receiving panel that is installed in a display apparatus for receiving a laser beam is too expensive to be widely spread.
FIG. 1 is a diagram of a conventional remote pointing apparatus using a laser beam. The conventional remote pointing apparatus includes a remote controller 100 that projects a laser beam 110, and a detection panel 122 that is fully installed behind a display panel 120 in order to detect a position at which the laser beam 110 is pointed.
When a user presses a light projection button 102 on the remote controller 100, the laser beam 110 is projected on the display panel 120 to indicate a position to be selected. The laser beam 110 is transmitted through the display panel 120 and is projected on the detection panel 122.
When the user presses a selection button 104 after locating the laser beam 110 at a desired position on the display panel 120, for example, at a menu to be selected, the current position of the laser beam 110 is detected through the detection panel 122.
A main body 130 recognizes the selected position and takes action according to a menu item corresponding to the recognized position.
FIG. 2 is a diagram of another conventional remote pointing apparatus using a laser beam. The conventional remote pointing apparatus shown in FIG. 2 includes sensors 200 and 202 instead of the detection panel 122 shown in FIG. 1. The sensor 200 that is arranged in the horizontal direction of a monitor generates a detection signal for indicating the abscissa of a laser beam 110 projected from a remote controller, and the sensor 202 that is arranged in the vertical direction of the monitor generates a detection signal for indicating the ordinate of the laser beam 110.
Since the conventional remote pointing apparatus shown in FIG. 1 needs the detection panel 122 that is installed behind the display panel 120 to fully cover the display panel 120, it is very expensive. In addition, as the size of the display panel 120 increases, the price also increases.
In the meantime, the conventional remote pointing apparatus shown in FIG. 2 is less expensive than that shown in FIG. 1, but the position of the laser beam 110 can be correctly detected only when the laser beam 110 is projected to be nearly perpendicular to the monitor. Accordingly, a user cannot freely use it.
A remote pointing method according to an embodiment of the present invention includes projecting an optical signal, which is periodically expanded and/or reduced around an origin of the optical signal at which a user points, from a remote controller onto a display panel, detecting whether the optical signal is received using three sensors that are installed around the display panel, and comparing a time point when each sensor detects the optical signal with the period of expansion and/or reduction of the optical signal, thereby detecting the position of the origin, that is, a position pointed at by a user.
Accordingly, an inexpensive remote pointing apparatus that a user can easily and freely use as if using a laser pointer is desired.